【作业】字符串操作练习：星座、凯撒密码、99乘法表

1、实例：输出12个星座符号，以反斜线分隔。

for i in range (12):
    print(chr(9800+i),end="  \\")

2、实例：恺撒密码的编码。

s = input("请输入凯撒的明文密码：")
for i in s:
    if ord("a") <= ord(i) <= ord("z"):
        print(chr(ord("a") + (ord(i) - ord("a") + 3) % 26),end='')
    else:
        print(i,end='')

 

3、输入姓名，格式输出：占4位、居中、不足4字的以空格填充。

s = input("请输入姓名(四个字以内)：")
if len(s) == 4:
    print("{}".format(s))
else:
    print("{0: ^4}".format(s))

4、格式化输出：中华人民共和国国内生产总值（GDP）689,136.89亿元（2015年）（千分位、2位小数，浮点数）。

print('中华人民共和国国内生产总值（GDP）：{0:,.2f}亿元（2015年）'.format(689136.89))

5、实例：打出99乘法表。

for i in range(1,10):
    for j in range(1,i+1):
        print("{}*{}={:2} ".format(j,i,i*j),end ='')
    print('')

 6、下载一首英文的歌词或文章，统计单词出现的次数，将所有,.？！替换为空格，将所有大写转换为小写。

write='''It was Mother’s Day.Sun Zheng thought he should do something for his mother.He decided to help his mother do some housework.After school he went to a shop to buy some food on his way home.
When he got home,he did his best to cook some nice food,though he couldn’t do the cooking well.Thenhe cleaned the room.He felt very tired,but he was very happy.
When his father and his mother came back and saw the clean rooms and dishes which weren’t so nice,they were very happy.They had their supper together.His mother said,"Thank you,my child!"''' 
write=write.replace('?',' ')
write=write.replace('!',' ')
write=write.replace(',',' ')
write=write.replace('.',' ')
write=write.lower()
print('he计数为：',write.count('he'))
print('and计数为：',write.count('and'))
print('文章内容：',write)

7、用webbrowser，uweb.open_new_tab('url')打开校园新闻列表。

import webbrowser
webbrowser.open_new_tab("news.gzcc.cn/html/xiaoyuanxinwen/")